1. Field of the Invention
The present invention relates generally to apparatus for holding, storing, and charging batteries.
2. Background of the Invention
Electronic equipment must receive a supply of power from a source of electricity. Most electronic equipment available today is powered directly from an alternating current (AC) source, such as a conventional wall outlet. Other, generally portable, devices are typically powered by batteries that must be periodically replaced after the batteries in use run down.
For convenience and economic reasons, rechargeable batteries are often employed in equipment that relies on batteries for power. Such batteries are well-known and come in several varieties, including Nickel-Cadmium(Ni-Cad) and Nickel metal Hydride (NiMH), to name just two. Such batteries are also available in a myriad physical configurations.
Some electronic equipment operates from both conventionally available AC power and battery power. For example, a cordless telephone typically includes a base station that is powered via an AC outlet and a cordless handset that is powered by a battery, or batteries (hereafter “batteries”). In most cordless telephones available today, the batteries that provide power to the cordless handset are rechargeable. When the cordless handset is mounted in the base station, the base station is configured to recharge the batteries in the cordless handset such that the batteries maintain the greatest possible amount of charge.
Despite the constant charging of the cordless handset batteries, it is not uncommon for the batteries to run down during prolonged use such that the handset can no longer be used. Some cordless telephone systems have, in view of this problem, standby batteries that are stored in the base station of the telephone and separately re-charged. Thus, when the cordless handset batteries run down, it is possible to simply swap the handset batteries with second, or stand-by, batteries that are stored and charged within the base station. The run down handset battery is then re-charged within the base station. In some cases, the batteries in the base station may also be used to provide stand-by power to the base station itself in the event of a power failure, wherein AC power is not available.
FIG. 1 is a schematic representation of selected portions of a conventional cordless telephone base station 100 and its interconnection with second or stand-by batteries. Base station 100 typically comprises a printed circuit board (PCB) 105 that includes electronic components that provide telephony functionality, along with assorted other features such as telephone number memory, caller ID functionality and display features. In addition, PCB 105 might also include a power supply 107, or at the very least, a means for distributing power, received from plug or transformer 110, which is plugged into a conventional AC wall outlet.
To support second, or standby, batteries, PCB 105 (or some other portion of the internal components of base station 100) includes a battery charging circuit 114 that includes output terminals 116a, 116b. Output terminals 116a, 116b are connected via wires 118 to a drawer 122 that includes terminals 120a, 120b. 
Drawer 122 typically has a shape that is consistent with the type of batteries that base station 100 and a handset use. Drawer 122 is preferably spring loaded (e.g., via springs 125) and biased to be pushed toward the exterior of base station 100. Drawer 122 is held in place within the body of base station 100 by way of a user-movable latch (not shown).
To replace or swap batteries, a user simply displaces the latch, which causes the drawer to automatically and at least partially eject itself from base station. This state is shown in FIG. 1. The user then removes the batteries present within drawer 122 and inserts rundown batteries and closes drawer 122. While this seemingly simple battery replacement procedure would not be expected to be potentially dangerous, there is, in actuality, the possibility that a user could be unexpectedly electrically shocked. Specifically, terminals 120a, 120b are, even when drawer 122 is in its open state, in contact with battery charger output terminals 116a, 116b via wires 118. Since base station 100 may be a telephone apparatus, it is typically connected to outside telephone wires. In addition, base station 100 is connected to an AC source of power through plug or transformer 110. Accordingly, in the event of a lightning strike to the power lines or telephone lines, or in the event of a malfunction in base station 100, any of which could cause unexpectedly high voltage/current levels within the circuitry of PCB 105, it is possible that such unexpectedly high voltage/current levels could be transferred across wires 118 and be present at terminals 120a, 120b with which a user may easily come into contact when performing a battery replacement procedure.
In view of the possible danger associated with replacing a battery in known devices, there is a need for improved battery storage, holding and recharging systems.